Investigating Minds 2009 RB

Morality and the Brain

2009-04-29T09:06:00.000-07:00

The issue of morality is something that has and will always be an integral component of progressive thought. Throughout history, the moral dilemma and the idea of right and wrong, has most commonly been explained through religion and philosophy. However, modern thinkers are trying to look beyond that to see where this moral sense comes from. How do we make moral decisions, and can they explained scientifically? Neurologists today, are now looking at this question through studies, which use brain imaging, on top of a number of observational techniques, to record any biological explanation of morality. This radiolab episode deals directly with this question, using four different experiments and studies.

The Trolley Problem:

This experimental research, performed by Joshua Greene, is centered on an idea posed by the philosophers Pilippa Foot and Judith Jarvis Thomson, called the “Trolley Problem.” This idea is comprised of two theoretical situations that spur a moral dilemma. One being the switch dilemma: A runaway trolley is hurtling down the tracks toward five people who will be killed if it proceeds on its present course. You can save these five people by diverting the trolley onto a different set of tracks, one that has only one person on it, but if you do this that person will be killed. Is it morally permissible to turn the trolley and thus prevent five deaths at the cost of one? Most people say, "Yes." The other is the footbridge dilemma: the trolley is headed for five people. You are standing next to a large man on a footbridge spanning the tracks. The only way to save the five people is to push this man off the footbridge and into the path of the trolley. Is that morally permissible? Most people say "No." The two situations lead to inquiry about why, in the switch case, it is permissible to kill one person in order to save the lives of five others, while in the footbridge case, killing the one person is completely unacceptable. Moreover, “how does everyone know (or “know”) that it is okay to turn the trolley but not okay to push the man off the footbridge?”

Study:

In Joshua Greene’s study, brain imaging was used to record the response people had to moral dilemmas like the ones just mentioned, as well as many others. He also divided the moral dilemmas into two categories, based on difficulty, recording not only the brain activity, but also the relationship between reaction time and the difficulty of the dilemma. He hypothesized that the difference between each situation is that, one case is “up-close-and-personal” while the other is impersonal. Greene predicted that brain imaging would indicate the differentiation in brain activity when responding to a personal case as opposed to an impersonal case. The study was a preliminary attempt to understand the question “are the moral truths to which we subscribe really full blown truths, mind-independent facts about the nature of moral reality, or are they… in the mind of the beholder?” Also, in moral dilemmas such as the one mentioned, why is it horrific and outrageous to react one way and completely acceptable to act another way. Through his testing he tries to support the theory that this phenomena is less about structured moral codes enforced through experience or evolution, and more about “the way our brains are wired up.” His hypothesis also argues that in personal dilemmas, a difference in reaction times for “yes” and “no” answers would indicate that there is different brain activity allowing the person to make that judgment.

Results:

When responding to a more personal moral dilemma, three emotional related brain regions: the posterior cingulate cortex, the medial prefrontal cortex, and the amygdala, were more active. Whereas, when a person responded to an impersonal dilemma, there was greater activity in areas associated with simple cognition: the dorsolateral prefrontal cortex, and the inferior parietal lobe. When reviewing response time, in relation to the brain images, it was shown that in cases where a person answered, “yes” to questions like the footbridge dilemma, there was intense cognitive brain activity in the dorsolateral prefrontal cortex, the inferior parietal lobe, as well as in the anterior cingulate cortex (associated with conflict), and their reaction time was extended; when a person answered “no” in cases like the footbridge dilemma, there was heightened emotional brain activity in the posterior cingulate cortex, medial prefrontal cortex, and the amygdala, and their reaction time was significantly faster.

These results suggest that moral judgments emerge from more than one neurological system. Going even further, it appears that these emotional and cognitive systems are essentially battling with each other, striving to control and influence the outcome of a moral decision. He arrived at this conclusion by using the localization of morally driven responses in the brain to watch neural activity, while simultaneously recording the time it takes one to make a decision; from this he presumed that shorter reaction times were indicative of the emotional brain systems dominating the cognitive process, while longer reaction times mean that the cognitive systems have overpowered the impulsive emotional response.

Based on his findings, Greene believes that profound moral positions are not, as commonly perceived, invented by humans, or God given, but rather that they may somehow be embedded in brain chemistry. He thinks that morality is fundamentally a product of the interaction between neurological systems. With this theory, Greene also considers that through the evolution of humanity, we have developed a stronger cognitive response to moral dilemma, and yet the less consequentialistic (philosophical view that moral judgment is a product of evaluating the consequences of the decision) response to moral dilemma, is still, very often, overriding.

Kiddie Morality:

This segment looks at how young children adhere, very early, to the moral universe. Through Dr. Judith Smetana research, it is clear that moral judgment for these children is not solely realized through the rules enforced by the adults around them. In addition to what they are taught, there seems to be certain moral concepts that are understood and driven by something innate. Smetana interviews pre-school children, asking them all kinds of questions that embody complex moral ideas, but are presented simply in terms that a young child can relate to. She asks:

-Who makes the rules here?

· The teacher.

-Can the teacher change the rules if they want to?

· Yes. She’s the teacher; she can do whatever she wants.

-Is there a rule about hitting at your school?

· Yes.

-Suppose the teachers agree that they don’t have a rule about hitting anymore, would it then be okay to hit?

· No. Because that would make somebody would feel bad.

-Is there a rule about sitting during lunch? Is that a rule the teacher could change?

· Yes. Yes, if she says okay you can stand up, you can do that... You have to listen to the teacher.

What she found was that with certain rules, the children felt that changing or deviating from the rule would be okay, and with others, the children expressed that it would not be okay to break them. In cases dealing with hitting, hurting, and teasing, the general consensus is that it would be wrong, even if the teacher did not see them or did not have a rule about hitting; whereas with rules like sitting in a circle during “circle time” or during lunch, the children felt that it would be acceptable if the rule was different or if there was not rule at all.

She also addresses how young children develop this moral sense, which could be partially innate, but is also largely discovered through experience. While most young children understand a lot rules and the conditions of the rules, they still often subside and break the rules, giving in to certain intrinsic urges. Researchers think that these defiant moments could be relating to their young underdeveloped sense of empathy. In one anecdotal story, a women describes watching her four-year-old son, in his classroom, make his best friend bleed by tackling him in front of the entire class. She explained that although it was extremely difficult to intervene when she saw how mortified her son was after the incident, it was important for him understand the emotional consequences of this kind of behavior.

The next story in this segment also looked at moral development from an experiential perspective. Two adults talked about the ways in which very specific events from their childhood, where they had diverged from their moral rules, continue to resonate even after so many years. They explained how they continue to feel guilt and regret about their poor moral judgments; although, in retrospect, those experiences have heavily shaped their moral sense and ability to empathize.

Controversy Surrounding the Neurological and Psychological Study of Morality

Morality has always been, for a number of reasons, highly controversial; even before there were any kinds of scientific theories or connections made. It deals with the way we understand “right” and “wrong”, and from this very subjective perception conflict spurs. Morality is also one of the most integral components of religion. Different religions affirm different explanations as to why/how morality should be incorporated into our lives. For instance, Christianity explains morality as the 10 commandments, physically handed down from God on a tablet. In this case, neurological research is in complete opposition with Christian convictions, because it essentially proposes that morality could be, in fact, a product of brain chemistry. Because most religious perspective on morality is so heavily rooted in history, something that radically defies the common belief the way the recent scientific studies do is bound to spark significant controversy and debate.

Resources

Greene, J. D. (2007). The secret joke of Kant's soul, in Moral Psychology, Vol. 3: The Neuroscience of Morality: Emotion, Disease, and Development, W. Sinnott-Armstrong, Ed., MIT Press, Cambridge, MA

Greene, J.D. (2003) From neural "is" to moral "ought": what are the moral implications of neuroscientific moral psychology? Nature Reviews Neuroscience, Vol. 4, 847-850

“Morality,” Radiolab, wnyc

Meditation and Neuroscience

2009-04-27T07:11:00.000-07:00

WIRED- 'Buddha on the Brain'

The 'science' of meditation...?

http://www.wired.com/wired/archive/14.02/dalai.html?pg=1&topic=dalai&topic_set=

The hot new frontier of neuroscience: meditation! (Just ask the Dalai Lama.)

The Dalai Lama has a cold. He has been hacking and sniffling his way around Washington, DC, for three days, calling on President Bush and Condoleezza Rice and visiting the Booker T. Washington Public Charter School for Technical Arts. Now he's onstage at the Washington Convention Center, preparing to address 14,000 attendees at the Society for Neuroscience's annual conference.

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The mood is tense. The State Department Diplomatic Security Service has swept the hallways for explosives. Agents stand at their posts.

The 14th incarnation of the Living Buddha of Compassion approaches the podium, clears his throat, and blows his nose loudly. "So now I am releasing my stress," he says. The audience dissolves into laughte.

The Dalai Lama is here to give a speech titled "The Neuroscience of Meditation." Over the past few years, he has supplied about a dozen Tibetan Buddhist monks to Richard Davidson, a prominent neuroscience professor at the University of Wisconsin-Madison. Davidson's research created a stir among brain scientists when his results suggested that, in the course of meditating for tens of thousands of hours, the monks had actually altered the structure and function of their brains. The professor thought the Dalai Lama would make an interesting guest speaker at the Society for Neuroscience's annual meeting, and the program committee jumped at the chance. The speech also gives the Tibetan leader an opportunity to promote one of his cherished goals: an alliance between Buddhism and science.

But the invitation has sparked a noisy row within the neuroscience community. To protest the talk, some scientists set up an online petition, which was immediately hacked by the pro-Dalai Lama faction. Others are boycotting the event or withholding their conference papers. Still others have demanded - unsuccessfully - time for a rebuttal.

All of which may explain the lama's ailment. "His Holiness' cold is a manifestation of the opposition of some scientists to his coming to the conference," a young Chinese Buddhist explains to me.

The protesters complain that the Tibetan leader isn't qualified to speak about brain science. They fret that he'll draw media attention away from important findings presented at the conference. Worst of all, his presence muddles the distinction between objective inquiry and faith. "We don't want to mix science and religion in our children's classrooms," says Bai Lu, a researcher at the National Institutes of Health, "and we don't want it at a scientific meeting."

One of the petition organizers, Lu Yang Wang, is even more blunt: "Who's coming next year?" he asks. "The pope?"

Richard Davidson, 54, is at once a distinguished scientist and an avid spiritual seeker. He became fascinated with meditation in the '60s. As a graduate student at Harvard, he channeled that interest into the study of psychology and neuroscience. In his spare time, he hung out with Ram Dass, Timothy Leary's former LSD research partner turned mystic. Davidson traveled to India for a meditation retreat, then finished his doctorate in biological psychology and headed to the University of Wisconsin, where he now directs the Waisman Laboratory for Brain Imaging and Behavior.

The Dalai Lama learned of Davidson's work from other scientists and in 1992 invited him to Dharamsala, India, to interview monks with extensive meditation experience about their mental and emotional lives. Davidson recalls the "extraordinary power of compassion" he experienced in the Dalai Lama's presence.

A decade later, he got a chance to examine Tibetan Buddhists in his own lab. In June 2002, Davidson's associate Antoine Lutz positioned 128 electrodes on the head of Mattieu Ricard. A French-born monk from the Shechen Monastery in Katmandu, Ricard had racked up more than of 10,000 hours of meditation.

Lutz asked Ricard to meditate on "unconditional loving-kindness and compassion." He immediately noticed powerful gamma activity - brain waves oscillating at roughly 40 cycles per second -�indicating intensely focused thought. Gamma waves are usually weak and difficult to see. Those emanating from Ricard were easily visible, even in the raw EEG output. Moreover, oscillations from various parts of the cortex were synchronized - a phenomenon that sometimes occurs in patients under anesthesia.

The researchers had never seen anything like it. Worried that something might be wrong with their equipment or methods, they brought in more monks, as well as a control group of college students inexperienced in meditation. The monks produced gamma waves that were 30 times as strong as the students'. In addition, larger areas of the meditators' brains were active, particularly in the left prefrontal cortex, the part of the brain responsible for positive emotions.

Davidson realized that the results had important implications for ongoing research into the ability to change brain function through training. In the traditional view, the brain becomes frozen with the onset of adulthood, after which few new connections form. In the past 20 years, though, scientists have discovered that intensive training can make a difference. For instance, the portion of the brain that corresponds to a string musician's fingering hand grows larger than the part that governs the bow hand - even in musicians who start playing as adults. Davidson's work suggested this potential might extend to emotional centers.

But Davidson saw something more. The monks had responded to the request to meditate on compassion by generating remarkable brain waves. Perhaps these signals indicated that the meditators had attained an intensely compassionate state of mind. If so, then maybe compassion could be exercised like a muscle; with the right training, people could bulk up their empathy. And if meditation could enhance the brain's ability to produce "attention and affective processes" - emotions, in the technical language of Davidson's study - it might also be used to modify maladaptive emotional responses like depression.

Davidson and his team published their findings in the Proceedings of the National Academy of Sciences in November 2004. The research made The Wall Street Journal, and Davidson instantly became a celebrity scientist.

Not everyone was impressed. Yi Rao, a professor in the neurology department at Northwestern University, dismisses Davidson's study as rubbish. "The science is substandard," he says. "The motivations of both Davidson and the Dalai Lama are questionable."

As a leader of those opposing the Dalai Lama's speech, Rao criticizes Davidson for being a "politically involved scientist" who engineered the Dalai Lama's invitation to lend scientific legitimacy to Buddhism and press the Chinese government to ease up on Tibet.

But the political critique cuts both ways. Rao is Chinese, as are more than half of the 544 cosigners of the petition protesting the Dalai Lama's lecture. Many in the neuroscience community believe that Chinese opposition to the speech is fueled by the Chinese government's long-running propaganda campaign against the Tibetan leader. "It's pretty transparent," Davidson says.

Still, the broader point of Rao's argument has undeniable force: Davidson's close personal relationship with the Dalai Lama is unseemly. Scientists are supposed to maintain professional distance from individuals and organizations that support their research and have a stake in the outcome. If Davidson were receiving corporate support to study the effects of ice cream on the brain's pleasure centers, he wouldn't hang out with Ben and Jerry. Yet he's frequently seen with the Dalai Lama, whom he clearly reveres.

Davidson bristles at this charge. "I tremendously value my relationship with His Holiness and feel it has benefited my research," he says with a thin smile. "I have no intention of giving it up."

The Dalai Lama's fascination with science dates to his childhood, when young Tenzin Gyatso (his birth name) found a brass telescope that had belonged to his predecessor. For years he has been meeting with leading figures in physics and biology to broaden his understanding. He's still scratching his shaved head over quantum mechanics.

The Tibetan leader believes that Buddhism and science have much in common. Both are investigative traditions that seek to explain reality. He admires the power of the scientific method and has famously stated his willingness to jettison Buddhist doctrines shown by science to be false. However, since much of Buddhist doctrine - reincarnation, for instance - is inherently untestable, many of the Dalai Lama's beliefs remain insulated from scientific critique.

Ultimately, Buddhists and scientists hold very different views of the universe. Buddhists believe that mental and physical realms have an equal claim on reality. That is, mental constructs that science considers imaginary are, to Buddhists, objectively real and perceptible. In contrast, neuroscientists are materialists. The mind can't be separated from the physical circumstances that give rise to it. In this regard, Davidson's views hew to the scientific mainstream. "I believe mind is an emergent property of brain," he says. "Mind depends upon brain." The Dalai Lama has agreed to set this point aside for the time being.

What Buddhism has to offer science is a way to examine consciousness from the inside - though it wouldn't normally be accepted as scientific. Neuroscience approaches the brain the same way Western science views all problems: from an external, objective perspective the Dalai Lama calls "third-person." Buddhist meditation provides an introspective, first-person way to study consciousness; meditators can report their findings to scientists. "If we very precisely look at when a thought arrives, what it does … all that is very empirical," Ricard said in a 2003 radio interview. "If different meditators reproduce the same descriptions," it "has the character of science because it's experimental."

As much as the Dalai Lama enjoys dabbling in science, he has a greater purpose: to alleviate suffering. Buddhism has an extensive toolkit of techniques intended to reduce misery and perfect humanity through quieting the mind and cultivating compassion. The Dalai Lama wants to extract these methods from their religious context and ground them in the science of the brain in the hope that they will be widely adopted.

On this, Davidson and the Tibetan leader agree. Kids take PE, Davidson points out. "Wouldn't it be wonderful if they also attended a class called ME - mental education? The scientific work we're doing is providing one small piece of that larger message."

Standing onstage at the Washington Convention Center, the Dalai Lama clears his throat one last time and addresses the Society for Neuroscience.

If there is a prepared speech, he's ignoring it. For the next 30 minutes, in broken English and through his interpreter, he riffs on his childhood interest in science. "Curiosity is part of my life, part of my self. Look at this body. Some areas have more hair, some less. Why?" He stresses the importance of ethics in pursuit of scientific answers. He's especially concerned that researchers are not paying enough attention to the development of "warmheartedness." Like charity, this quality begins at home. "Come home and be with your wife, your husband, or your children," he beseeches the assembled neuroscientists, "and feel happy!"

A few minutes later, he departs in a swarm of aides and security personnel.

Opponents of the Dalai Lama's appearance fear a breach in the barrier between science and religion. For now, though, brain researchers are staying on their side of the wall. Davidson is the first to admit that his studies haven't proven that compassion is a skill to be cultivated - though clearly he believes it is. "The honest answer is, we don't know," he says, "which is why longitudinal studies are necessary."

Such research is just beginning. Experiments that will follow novices through months of intensive training - the only way to test whether meditation actually changes the brain - are starting up at UC San Francisco and UC Davis. Meditation research is blossoming at a dozen universities, including Harvard and Princeton.

Amid the flurry of Buddhist-inflected inquiry, however, there's a risk that researchers' beliefs and desires will influence the results of their experiments. Already the Mind & Life Institute, an organization cofounded by the Dalai Lama to foster dialog between researchers and mystics, sponsors summer programs that are part scientific discourse, part Buddhist retreat. These programs, Davidson says, are "producing a hybrid discipline of dharma practitioners and scientists." The scientific method is designed to counteract the bias of faith, but adulterating scientific objectivity with a first-person perspective makes it more likely that researchers will see what they want to see.

A few days before the Dalai Lama addressed the Society for Neuroscience, he stood before a similarly eminent crowd at the Mind & Life Institute's 13th annual meeting. The audience of 2,500 consisted mostly of scientists and clinicians, yet the mood was more dharma than Darwin. Sessions opened to the guttural chants of Tibetan liturgical music. Everyone stood and bowed when His Holiness entered the room.

During one presentation, Duke University professor of medicine Ralph Snyderman paused to tell His Holiness, "This is one of the most wonderful moments of my life, being here with you." It was a touching gesture. It also crystallized the dilemma. Scientists can try to test the validity of the Dalai Lama's first-person perspective. But if they allow reverence for him to cloud their judgment, they will cease to be scientists and take rebirth as something quite different: acolytes.

John Geirland (geirland@aol.com) wrote about radio telescopes in issue 12.02.

Article:

http://psyphz.psych.wisc.edu/web/pubs/2004/meditators_synchrony.pdf

BIG-HEADED with BIG BRAINS!!!

2009-04-26T16:29:00.000-07:00

WHAT IS SELF-ESTEEM?
http://kidshealth.org/kid/feeling/emotion/self_esteem.html

DETAILS CONCERNING DR.SONIA LUPIEN'S RESEARCH
http://reporter-archive.mcgill.ca/Rep/r3016/lupien.html

DR. SONIA LUPIEN'S "STRESS, MEMORY, AND AGING" VIDEO

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RELATED BBC SITES

Low self-esteem 'shrinks brain'

By Pallab Ghosh
BBC Science Correspondent

Brain size was measured

People with a low sense of self worth are more likely to suffer from memory loss as they get older, say researchers.

The study, presented at a conference at the Royal Society in London, also found that the brains of these people were more likely to shrink compared with those who have a high sense of self esteem.

Dr Sonia Lupien, of McGill University in Montreal surveyed 92 senior citizens over 15 years and studied their brain scans.

She found that the brains of those with low self-worth were up to a fifth smaller than those who felt good about themselves.

These people also performed worse in memory and learning tests.

Retraining

Dr Lupien believes that if those with a negative mind set were taught to change the way they think they could reverse their mental decline.

He said: "This atrophy of the brain that we thought was irreversible is reversible - some data on animals and some data on humans shows that that if you enrich the environment if you change some factors this brain structure can come back to normal levels"

Researchers are studying which psychological treatments work best.

According to Dr Felicia Huppert of Cambridge University - the early signs are that fairly simple techniques can have an enormous impact:

"There are interventions which talk about focusing on positive things in everyday life and savouring good moments even at times when life is difficult little tiny things may give you pleasure so there are skills involved in how to derive pleasure from the ordinary things in life".

'Reversed'

According to Dr Lupien, the fear of memory loss may be a self fulfilling prophesy as anxiety leads to negative thinking which leads to mental impairment.

"If you always think it's normal to lose something, then you will never work to increase it because doctors have always told you that. I'm saying that it is not normal.

"So this might impact positvely on the public by saying that its possible to impact on increasing your memory performance and by saying that it is normal to have a fulfilling life, we may be able to increase self esteem among the general public - and prevent a lot of these deficits related to age".

Willpower: A Game of Strategy

2009-04-12T18:48:00.001-07:00

http://www.npr.org/templates/story/story.php?storyId=102728123

To the Brain, God is Just Another Guy

2009-04-11T05:12:00.000-07:00

http://www.npr.org/templates/story/story.php?storyId=101617951

Below is the published findings of these experiments by Kapogiannis, et al:
http://www.clarin.com/diario/2009/03/10/um/estudiofereligiosa.pdf

These are just some examples of the God Experiments (this is some background material for my paper, so you do not have to read this):
http://discovermagazine.com/2006/dec/god-experiments/?searchterm=god%20experiments

Schizophrenia: The Curse That's Almost a Blessing

2009-04-07T20:58:00.000-07:00

http://discovermagazine.com/2007/dec/schizophrenia-the-curse-thats-almost-a-blessing/?searchterm=schizophrenia

What Can Magic Teach Us About The Brain?

2009-03-29T13:48:00.000-07:00

http://www.sciam.com/article.cfm?id=magic-neuroscience-cognition-illusions

Or Listen At:

http://www.npr.org/templates/story/story.php?storyId=93465269

Quick Thinking and Intelligence

2009-03-28T01:15:00.001-07:00

http://www.npr.org/templates/story/story.php?storyId=102169531

Read and Listen.

The Study:

The study is the first to analyze genetic and environmental factors that affect brain fiber architecture and its genetic linkage with cognitive function. It assessed white matter integrity voxelwise (voxel, is a volume element, representing a value on a regular grid in three dimensional space—analogous to a pixel) using diffusion tensor imaging at high magnetic field (4 Tesla), in 92 identical and fraternal twins. White matter integrity, quantified using fractional anisotropy (FA), was used to fit structural equation models (SEM) at each point in the brain, generating three-dimensional maps of heritability. The study visualized the anatomical profile of correlations between white matter integrity and full-scale, verbal, and performance intelligence quotients (FIQ, VIQ, and PIQ).

The quantifiable measure of white matter integrity related to cognition—fractional anisotropy (directional variability) of diffusion is higher in heavily myelinated fiber tracts, and increases with progressive myelination during development. Increases in myelination and larger axonal diameter are associated with increased neuronal conduction speed and may support better cognitive function. Fractional anisotropy correlates with intellectual performance in normal subjects and is reduced by degenerative processes that impair axonal fiber integrity.

The study was comprised of 92 twins, 23 pairs of identical (11 male pairs and 12 female pairs) and fraternal (10 male pairs and 13 female pairs). Each person was tested using the Wechsler Adult Intelligence Scale and then scanned using diffusion tensor imaging in order to create a spatially detailed map of white matter integrity.

Methods:

Using the Wechsler Adult Intelligence Scale, three verbal (information, arithmetic, and vocabulary) and two performance (spatial and object assembly) subtests were examined for the purposes of this study. Each subtests produced a raw score and verbal (VIQ), performance (PIQ) and full-scale (FIQ) intelligence quotient standardized scores were derived. In this study the IQ scores for identical and fraternal twins were not significantly different.

Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that enables the measurement of the restricted diffusion of water in tissue in order to produce neural tract images instead of using this data solely for the purpose of assigning contrast or colors to pixels in a cross sectional image. The idea of using diffusion data to aid in the production of images of neural tracts curving through the brain.

More extended diffusion tensor imaging (DTI) scans derive neural tract directional information from the data using 3D or multidimensional vector algorithms based on three, six, or more gradient directions, sufficient to compute the diffusion tensor. The diffusion model is a rather simple model of the diffusion process, assuming homogeneity and linearity of the diffusion within each image-voxel. From the diffusion tensor, diffusion anisotropy measures such as the Fractional Anisotropy (FA), can be computed. Moreover, the principal direction of the diffusion tensor can be used to infer the white-matter connectivity of the brain (i.e. tractography; trying to see which part of the brain is connected to which other part).

The principal application is in the imaging of white matter where the location, orientation, and anisotropy of the tracts can be measured. The architecture of the axons in parallel bundles, and their myelin sheaths, facilitate the diffusion of the water molecules preferentially along their main direction.

When an IQ score was significantly correlated with FA ( with FDR <0.05), intelligence as well as estimate the genetic and environmental contributions to the correlations between FA and IQ in the same set of subjects. If the correlation between the voxel value of FA in one twin and the level of IQ in the other twin is greater in identical pairs than in fraternal pairs, the excess in the identical correlation over the fraternal correlation is then assumed to be attributed to common genetic factors that mediate both white matter integrity and intelligence.

Given the correlation between IQ scores and white matter integrity in similar regions, it is plausible that overlapping sets of genes may influence IQ measures and fiber architecture. A way to determine this is to use a measure of one trait in one twin to predict the level of the other trait in the other twin. If a prediction can be made with greater precision in identical twins tan fraternal, then a common setoff genes must be involved.

Findings:

-white matter integrity under strong genetic control, with highest heritability in parietal brain regions

White matter integrity (FA) was under strong genetic control in all posterior white matter regions and was highly heritable in bilateral frontal (a2 = 0.55, p = 0.04, left; a2 = 0.74, p = 0.006, right), bilateral parietal (a2 = 0.85, p < a2 =" 0.84," a2 =" 0.76," p =" 0.003)" p =" 0.04" p =" 0.01">

-white matter integrity linked to intellectual performance, with correlations as high as 0.3-0.4 between performance IQ and white matter integrity

-using cross-trait mapping, implicated the same genes as mediating the correlation between IQ and white matter integrity—suggesting a common physiological mechanism for both.

FA and FIQ, PIQ or OBJ scores were influenced by an overlapping set of genes in the cingulum and isthmus of the corpus callosum, the cerebral peduncles, the posterior limbs of the internal capsule and the left posterior thalamic radiation/optic radiation, the right superior fronto-occipital fasciculus and the anterior, superior and posterior corona radiate bilaterally. These correlations were mediated by common genetic factors. The fiber systems whose integrity was most tightly linked with IQ include several with critical roles in visuospatial processing. FA may reflect underlying levels of axonal myelination, which may account for differences in reaction times, processing speed and intellectual performance across subjects.

Issues and Questions:

Limited by age—narrow age range, not model influence of age on heritability

This kind of DTI scan can help to detect Alzheimer’s (slow down of neural pathways) and could also help to determine whether or not new medication for Alzheimer’s is working.

The question of measuring intelligence—in order for this study to stand one must accept the use and validity of standardized intelligence tests.

Autism and Mirror Neurons

2009-03-27T08:25:00.000-07:00

Autism Reveals Social Roots of Language

by Jon Hamilton

Listen Now add to playlist

Bill Cotton, Colorado State University

Temple Grandin, who teaches animal science at Colorado State University and is autistic, says it's taken her a lifetime to speak in a way that sounds natural to others.

WHAT LIES BENEATH: A multimedia interactive shows language at work on many levels.

(Download the Latest Flash Player)

Q&A with Temple Grandin

July 9, 2006
Grandin talks about what parents can do to help autistic children communicate better.

Weekend Edition Sunday, July 9, 2006 · People with autism often struggle to learn language, and they also struggle with personal relationships.

Scientists say that's probably not a coincidence.

There's growing evidence that language depends as much on the brain circuits that help us navigate a cocktail party as those that conjugate verbs.

One of the people who believes that evidence is Temple Grandin. She teaches animal science at Colorado State University and has written several best-selling books. She's also autistic.

Grandin says it has taken her most of her life to reach the point where she can speak with other people in a way that sounds natural. She says that's because she's had to learn language without the social abilities most people have.

Grandin didn't begin speaking until she was 3 ½ years old. Her first words referred to things, not people, she says.

"I'd point at something that I wanted, you know like a piece of candy or whatever, and say, 'there,'" Grandin says.

She wasn't using language to reach out to her parents or to other children, the way most kids do, so she didn't have the same motivation to talk.

A Tool for Information, or Attention?

When Grandin finally did become interested in words, it was because they provided a way to get information, not attention.

"When I was in third grade, I had trouble with reading, so mother taught me how to read," she says. It opened up a world full of "so many interesting things," she recalls: "I used to like to get the World Book Encyclopedia and read it."

But the encyclopedia taught her little about using language to make friends. Even when she got to high school, chit-chat and gossip meant nothing to her.

She says that made her teenage years the worst part of her life. "Kids teased me, called me tape recorder because when I talked it was kind of like just using the same phrases."

She also kept talking, without letting other people respond.

Grandin and many others with autism have no problem with the mechanics of language, says Dr. V.S. Ramachandran, a neuroscientist at University of California, San Diego. But they don't understand what's really going on in many conversations.

"That's one of the hallmarks of autism," he says, "difficulty with social interaction, manifest both in spoken language and in just lack of empathy. The ability to understand other minds would be one way of describing it."

The Role of Mind Reading

Ramachandran says it's hard to use language if you don't have any idea what someone else is thinking and feeling.

That may seem obvious. But in the past, researchers have treated language as if it were primarily a system of rules. They assumed that people spoke because every human brain came pre-wired with a "universal grammar."

Now, a growing number of researchers, including Ramachandran, argue that the social and emotional aspects of language are at least as important as the rules for stringing words together.

Emotional Neurons

Ramachandran says one reason for the new thinking is a new understanding of the human brain. He says it's become clear that babies' brains are programmed to imitate.

"You stick your tongue out at a newborn baby, very often the newborn baby will stick its tongue out," he says.

Similarly, babies return smiles and often make sounds when someone speaks to them.

A few years ago, scientists found a biological explanation for this phenomenon: specialized brain cells called mirror neurons.

These neurons fire when you do things such as sticking your tongue out. They also fire when you watch someone else stick their tongue out.

And mirror neurons can reflect emotions as well as physical actions. Experiments show that some of the same cells that fire when we feel pain also fire when we see another person in pain.

But people with autism appear to have faulty mirror neurons. That may be why they have trouble putting themselves in someone else's shoes. And Ramachandran says without that ability, a lot of what you can accomplish with language disappears.

"You have to be aware of the effects that your words are having on the other person's mind," he says. Otherwise, how could we use words to manipulate other people?

Picking Up Non-Verbal Cues

Temple Grandin has learned to compensate for her difficulty.

Early in her career, she spoke to people on the phone instead of face to face. That way she didn't miss messages conveyed through eye contact or body language.

But even on the phone, people may not say what they mean. The phrase "I'm fine" sometimes means just the opposite.

So Grandin taught herself to listen very closely to a person's tone of voice.

"When I had a client that I thought might be angry with me, I'd call him up just so I could listen to his voice," she says. "If it had a certain little whine sound in it I'd go, 'Oh he's still angry with me.'"

Over time, Grandin has developed a catalogue of signals she uses to figure out what people are thinking. She checks to see if they are fidgeting during a lecture, or making eye contact during a conversation, or folding their arms during an argument -- emotional cues most of us register automatically.

"I always keep learning," Grandin says. "People ask for the single magic breakthrough. There isn't one. I keep learning every day how I think and feel is different. It's all through logic, trial and error, intellect."

Intellect can only take her so far, though. Grandin says she still has trouble with certain types of conversations.

"Just a couple of years ago I went out to dinner with some salesmen, and these people were absolutely totally social," she says. "They talked for three hours about sports-themed nothing. There was no informational content in what they were talking about. It was a lot of silly jokes about the color of medication and the color of different team mascots. It was boring for me."

Social Motivation for Language

The salesmen were using language as a way of bonding with one another -- not a way to share information. Scientists say this sort of behavior may explain how humans developed language in the first place.

Bonding is something most animals do. For example, apes bond by grooming each other. And one theory has it that early humans began to augment their grooming with affectionate gestures and sounds that eventually led to primitive language.

Ramachandran says there are some gaps in that hypothesis. Like how people got from grunts to grammar.

"The difficult part is to try to disentangle the notion that emotional empathy merely gives you motivation, a reason to talk to somebody, versus an absolutely critical role in the emergence of language," he says.

Ramachandran suspects it's the latter because empathy is what allows people to understand the intention behind an action or a phrase.

For example, he says, when we see someone reach for a peanut, empathy helps us decide if they intend to eat it, or throw it at us. And when we hear someone use a string of words, empathy tells us whether to take the words literally or figuratively.

Ramachandran says people who lack empathy also lack the ability to read another person's intentions -- whether physical or linguistic.

"Not only do they have problems understanding an action like reaching for a peanut," he says, "but also a metaphor like reaching for the stars."

Grandin doesn't use metaphors very often, even though she has mastered the mechanics of language. Grandin says she will never fully understand the social aspects of language, including other people's intentions. And that means language will never offer her more than a rough translation of what other people are trying to say.

Produced by NPR's Anna Vigran

The Study done by Ramachandran:

"EEG evidence for mirror neuron dysfunction in autism spectrum disorder"

http://cbc.ucsd.edu/ramapubs.html

2. Materials and methods
2.1. Subjects
Our original sample consisted of 11 individuals with
ASD and 13 age- and gender-matched control subjects. All
subjects in the study were male. The ASD group was
composed of ten individuals diagnosed with autism and one
individual diagnosed with Asperger ’s syndrome. One
subject with autism and two control subjects were excluded
prior to analysis due to excessive movement artifacts that
resulted in an inability to obtain sufficient EEG data. One
additional control subject was excluded prior to analysis due
to a technical malfunction in the EEG system. Therefore,
our final sample consisted of 10 individuals with ASD and
10 age- and gender-matched controls. Subjects ranged in
age from 6–47 years (ASD: M = 16.6, SD = 13.0; Control:
M = 16.5, SD = 13.6; t (18) = 0.017, P N 0.98). One
individual was left handed in the ASD group, while in the
control group 3 individuals were left-handed.
ASD subjects were recruited through the Cure Autism
Now Foundation, the San Diego Regional Center for the
Developmentally Disabled, and the Autism Research
Institute. Control subjects were recruited through the UCSD
Center for Human Development subject pool and the local
community. Individuals were included in the ASD group if
they were diagnosed with either autism or Asperger ’s
syndrome by a clinical psychologist. Subjects met DSM-
IV criteria for a diagnosis of Autistic disorder or Asperger’s
disorder [3]. In addition, subjects in the ASD group
exhibited the following diagnostic behaviors at the time of
testing, including, but not limited to, awkward use of
pragmatics, intonation, and pitch in communication, lack of
initiation of social interactions, and obsessive preoccupation
with the order and specific details of the study. All subjects
were considered high-functioning, defined as having age
appropriate verbal comprehension and production abilities
and an IQ greater than 80 as assessed by either school
assessments or psychometric evaluations from a clinician.
Subjects without age appropriate verbal comprehension and
production abilities were excluded from the study. Subjects
were given age-appropriate consent/assents (for subjects
under the age of 18). In addition, in order to ensure that
subjects understood the procedure and the tasks involved, a
picture board was created and the study was fully explained,
in age-appropriate language, prior to the subjects’ partic-
ipation. This project was reviewed and approved by the
UCSD Human Research Protections Program.

2.2. Procedure
EEG data were collected during four conditions: (1)
Moving own hand : Subjects opened and closed their right
hand with the fingers and thumb held straight, opening and
closing from the palm of the hand at a rate of approximately 1
Hz. Subjects watched their hand at a comfortable viewing
distance, the hand held at eye level. (2) Watching a video of a
moving hand : Subjects viewed a black and white video of an
experimenter opening and closing the right hand in the same
manner as subjects moved their own hand. Videos were
presented at a viewing distance of 96 cm, and the hand
subtended 58 of visual angle when open and 28 when closed.
The hand was medium gray (8. 6 cd/m2) on a black
background (3.5 cd/m2). (3) Watching a video of two
bouncing balls : two light gray balls (32.9 cd/m2) on a black
background (1.0 cd/m2) moved vertically towards each other
touched in the middle of the screen then moved apart to their
initial starting position. This motion was visually equivalent
to the trajectory taken by the tips of the fingers and thumb in
the hand video. The ball stimulus subtended 28 of visual angle
when touching in the middle of the screen and 58 at its
maximal point of separation. (4) Watching visual white noise :
full-screen television static (mean luminance 3.7 cd/m2) was
presented as a baseline condition. All videos were 80 s in
length and both the ball and hand videos moved at a rate of 1
Hz. All conditions were presented twice in order to obtain
enough clean EEG data for analyses and the order of the
conditions was counterbalanced across subjects, with the
constraint that the self-movement condition always followed
the watch condition so that the subjects had a model on which
to base their movement.
To ensure that subjects attended to the video stimuli during
the watching hand movement and bouncing balls conditions,
they were asked to engage in a continuous performance task.
Between four and six times during the 80-s video, the stimuli
stopped moving for one cycle (a period of 1 s). Subjects were
asked to count the number of times stimuli stopped moving
and report the number of stops to the experimenter at the end
of the block.

2.3. EEG data acquisition and analysis
Disk electrodes were applied to the face above and below
the eye and behind each ear (mastoids). The mastoids were
used as reference electrodes. Data were collected from 13
electrodes embedded in a cap, at the following scalp
positions: F3, Fz, F4, C3, Cz, C4, P3, Pz, P4, T5, T6, O1,
and O2, using the international 10–20 method of electrode
placement. Following placement of the cap, electrolytic gel
was applied at each electrode site and the skin surface was
lightly abraded to reduce the impedance of the electrode-
skin contact. The impedances on all electrodes were
measured and confirmed to be less than 10 KV both before
and after testing. Once the electrodes were in place, subjects
were seated inside an acoustically and electromagnetically
shielded testing chamber.
EEG was recorded and analyzed using a Neuroscan
Synamps system (bandpass 0.1–30 Hz). Data were collected
for approximately 160 s per condition at a sampling rate of
500 Hz. EEG oscillations in the 8–13 Hz frequency
recorded over occipital cortex are influenced by states of
expectancy and awareness [31]. Since the mu frequency
band overlaps with the posterior alpha band and the
generator for posterior alpha is stronger than that for mu,
it is possible that recordings from C3, Cz, and C4 might be
affected by this posterior activity. Therefore, the first and
last 10 s of each block of data were removed from all
subjects to eliminate the possibility of attentional transients
due to initiation and termination of the stimulus. A 1-min
segment of data following the initial 10 s was obtained and
combined with the other trial of the same condition,
resulting in one 2-min segment of data per condition. Eye
blink and eye and head movements were manually
identified in the EOG recording and EEG artifacts during
these intervals were removed prior to analysis. Data were
coded in such a way that the analysis was blind to the
subjects’ diagnosis. Data were only analyzed if there was
sufficient clean data with no movement or eye blink
artifacts. For each cleaned segment, the integrated power in
the 8–13 Hz range was computed using a Fast Fourier
Transform. Data were segmented into epochs of 2 s
beginning at the start of the segment. Fast Fourier Trans-
forms were performed on the epoched data (1024 points). A
cosine window was used to control for artifacts resulting
from data splicing.
Two measures of mu suppression were calculated. First,
we calculated the ratio of the power during the observed
hand movement and self hand movement conditions relative
to the power during the baseline condition. Second, we
calculated the ratio of the power during the observed and
self hand movement conditions relative to the power in the
ball condition. A ratio was used to control for variability in
absolute mu power as a result of individual differences such
as scalp thickness and electrode impedance, as opposed to
mirror neuron activity. The ratio to the ball condition was
computed in order to control for the attention to counting or
any effects due to stimulus stopping during the continuous
performance task and processing of directional motion.
Since ratio data are inherently non-normal as a result of
lower bounding, a log transform was used for analysis. A
log ratio of less than zero indicates suppression whereas a
value of zero indicates no suppression and values greater
than zero indicate enhancement.

3. Results
3.1. Behavioral performance
To ensure that the subjects were attending to the stimuli,
during the hand and ball conditions, they were asked to
count the number of times the stimuli stopped moving.
Since all subjects performed with 100% accuracy on this
continuous performance task, we infer that any differences
found in mu suppression are not due to differences in
attending to the stimuli.

3.2. Mu suppression
Power in the mu frequency at scalp locations correspond-
ing to sensorimotor cortex (C3, Cz, and C4) during the self-
initiated action and watching action conditions was com-
pared to power during the baseline (visual white noise)
condition by forming the log ratio of the power in these
conditions for both groups (Figs. 1A, B). Although data
were obtained from electrodes across the scalp, mu rhythm
is defined as oscillations measured over sensorimotor
cortex, thus only data from C3, Cz, and C4 are presented.
The control group (Fig. 1A) showed significant suppres-
sion from baseline in mu oscillations at each electrode during
both the self-initiated hand movement condition (C3 t (9) =
3.97, P b 0.002; Cz t (9) = 2.85, P b 0.01; C4 t (9) =
4.00, P b 0.002) and observed hand movement condition
(C3 t (9) = 3.99, P b 0.002; Cz t (9) = 3.21, P b 0.005; C4
t (9) = 2.78, P b 0.01). The ASD group (Fig. 1B) also
showed significant mu suppression during the self-initiated
hand movement condition (C3 t (9) = 2.27, P b 0.03; Cz
t (9) = 1.91, P b 0.05; C4 t (9) = 2.50, P b 0.02). Unlike
controls, the ASD group did not show significant suppres-
sion during the observed hand movement condition (C3
t (9) = 0.64, P N 0.25; Cz t (9) = 0.98, P N 0.15; C4
t (9) = 0.74, P N 0.20). The failure to find suppression in
the ASD group was not due to differences in baseline mu
power (C3 t (9) = 0.99, P N 0.30; Cz t (9) = 0.69, P N
0.50; C4 t (9) = 0.47, P N 0.50). Lastly, neither group
showed significant suppression from baseline during the
non-biological motion (bouncing balls) condition (ASD:
C3 t (9) = 0.73, P N 0.20; Cz t (9) = 0.49, P N 0.65; C4
t (9) = .25, P N 0.40; Control: C3 t (9) = 1.45, P N 0.08;
Cz t (9) = 0.54, P N 0.30; C4 t (9) = 0.00, P N 0.50).

2009-03-04T20:35:00.000-08:00

Early descriptions of dreams and papers on the nature of dreaming suggest that color was commonly present in dreams before the 20th century (Schwitzgebel, 2003). Before the development of scientific psychology, even scholars such as Aristotle and Descartes, who were at some point interested in dreams, generally acknowledged or assumed that dreams were in color. However, studies from 1915 through to the 1950s suggested that the vast majority of dreams are in black and white, which many people attribute to the rise of black and white media. On the other hand, studies from the 60s and later (when colored media was prominent) suggested that up to 83% of dreams contain some color (Robson, 2008).

The Study:

Eva Murzyn (2007) focused on whether the influence of black and white media had any affect on the reported color of dreams. The subjects (30 females, 30 males; half under 25, the other half over 55) were asked:

· the age at which the participant was first exposed regularly to black and white media and/or colored media (on a following scale: 0–3 years old, 4–6, 7–10, 11–14, 15 years and over, never)

· the number of hours spent currently watching TV

· the percentage of programs watched in black and white.

For 10 days, the participants were asked to record the number of dreams they remembered when they woke up and answered six yes-no questions about the color type of each dream. The answers to these questions allowed Murzyn to classify the dream into on of four main categories: color, grayscale, mixed (containing both colored and grayscale elements) and neither.

The Results:

Out of the 30 participants under the age of 25;

All had frequent access to color television and film by the age of 6, most of them having such access before the age of 4.
Their results indicated that 21 participants had colored dreams, 6 had dreams with a mixture of both color and grayscale and 3 were unsure.

Out of the 30 participants over the age of 55;

· None of the participants had access to color media before the age of 7, and 22 participants indicated they had gained access to black and white media before colored media.

· Their results showed that only 8 people indicated they dream in color, 4 said they only have grayscale dreams and 12 mentioned having both types.

The overall results revealed that people who were exposed to black and white media before color media experienced more grayscale dreams than people with no such exposure.

Even in the group with black and white media experience, the average percentage of grayscale dreams experienced in this experiment was much lower than the proportions typically reported in the 1940’s and 1950’s. This difference is most likely due to the influence from color media, which has been the dominant media type for at least the last 40 years. Without black and white film media, scholars such as Aristotle and Descartes might not have thought that something colored may perhaps be represented in the mind as black and white. It would be natural to assume that since the things dreamed about are colored in real life, they should be colored in dreams. However, with the rise black and white media in the early twentieth century, people recognized that the images in their dreams resembled the images in black and white media.

Controversy:

Murzyn (2007) implies that the older group, now are over 55 years of age, has retained at least some of their grayscale dreaming patterns despite a long and intense color media exposure. However, the older participants recalled dreams less often than the younger group. Their dream reports also contained significantly less visual imagery which could lead to mislabeling dreams as grayscale. Because each participant was asked to record the color type of their dream the moment they wake up, many results could be also skewed due to memory errors.

Every day a person with the ability to see observes the world around them in full color. Because of this, Schwitzgebel (2003) suggests that it seems odd to suppose that what an individual sees in a movie or on the television screen would affect whether they dream about them in color. Despite their cultural significance, it seems unlikely that film and television would transform the dreams we have of the colored world around us into dreams of black and white. He believes that it may be more reasonable to assume, that the reporting of dreams that changed rather than their content.

Resources:

Murzyn, E. (2008). Do we only dream in colour? A comparison of reported dream colour in younger and older adults with different experiences of black and white media. Consciousness and Cognition, 17(4), 1228-1237.

O'Connor, A. (2008). The claim: Some people dream only in black and white. Retrieved March 1, 2008, from http://www.nytimes.com/2008/12/02/health/02real.html?_r=2&ref=health

Okada, H. (2005). Individual differences in the range of sensory modalities experienced in dreams. Dreaming, 15(2), 106-115.

Robson, D. (2008, ). ^{It's black and white: TV influences your dreams}. Message posted to http://www.newscientist.com/article/dn14959-its-black-and-white-tv-influences-your-dreams.html

Schwitzgebel, E. (2001). Why did we think we dreamed in black and white? Studies in History and Philosophy of Science, 33(4), 649-660.

Schwitzgebel, E. (2006). Do we dream in color? cultural variations and skepticism. Dreaming, 16(1), 36-42.

Jazz Improvisation Deactivates Brain!

2009-03-02T20:53:00.000-08:00

Jazz Improvisation on the Brain: an fMRI study.

Background
This NPR story talked about a recent study (published in February of 2008) dealing with Jazz improvisation on the brain; the description on the NPR page, however, is a little misleading as far as to the content of the program and the content of the experiment.

The Study
Six jazz pianists were studied in an fMRI machine. All right handed, healthy, “normal” hearing males, 21-50 years old (mean 34.2yrs), full-time professional musicians. They were accompanied by a pre-recorded quartet that played straight into their headphones, along with the sounds from their specially-designed fMRI keyboards that are not and cannot be induced to be magnetic (non-ferromagnetic) and only outputs MIDI information; is full-sized and specially designed, played a high-quality piano sample. Subjects used only right hand, and saw the keyboard through a series of mirrors to where it was propped up on their legs. There was no mechanical restraint.

Two block-designed test paradigms. First paradigm: Scales. Designed to test brain during a highly constrained situation but of low technicality. Right-hand only. Control task: play scale. Improv task: Play improv, but only use quarter notes and only notes in the scale. Number of notes, note range, key, and technical requirements all accounted for and remaining unchanged. 1 minute each, 30 second rest. 6 blocks total (3 scale, 3 improv)

Second Paradigm: Jazz. All were given a 12-bar musical piece to memorize. In the control condition, they played that. In the Jazz control, they were asked to improv to the chord progression of the pre-recorded accompaniment. The condition for the improvisation was that it should follow the style of the melody, and the “improvisation should be consistent with one another.” (in order to minimize variations in number of notes played, rhythmic complexity, or stylistic approach). Each block 1 minute, 5 control blocks, 5 improv blocks, and 9 non-performance auditory blocks (for use in a separate manuscript), with 20-second rest between each.

The Findings

fMRI analysis: “Significant” activation was considered those brain functions that were both greater than control and resting baseline. Significant deactivation was that with lower activation in comparison to these two conditions.Both paradigms (Jazz and Scale) have “strikingly similar results…a highly congruous pattern of activations and deactivations in prefrontal cortex, sensorimotor and limbic regions of the brain." Activation during improv was generally coupled with deactivation in control, and vice versa.

The Brain Areas:
Prefrontal cortex (playing a role of sense of self?—widespread deactivation. lateral prefrontal regions: LOFC (making sure your behaviors fit in with society?) & DLPFC (planning and step-by-step implementations). Almost all of lateral prefrontal cortices, but focal activation of frontal polar portion of the medial prefrontal cortex (keeping a goal while doing various things)

Neocortical Areas (mediate organization and execution of performance)—broad increase of activity: sensory areas: anterior portions of superior and middle temporal gyri (STG and MTG), including anterior portions of the superior temporal sulcus (STS), inferior temporal, fusiform and lateral occipital gyri, as well as inferior and superior parietal lobules and the intervening intraparietal sulci.

premotor and motor areas: selective activation: ventral and dorsal lateral premotor areas, supplementary motor area and portions of the primary motor cortex. The anterior cingulate cortex, cingulate motor area, right lateral cerebellar hemisphere, and vermis were activated as well extensive deactivation of dorsolateral prefrontal and lateral orbital regions with focal activation of the medial prefrontal (frontal polar) cortex.

Limbic and Paralimbic Regions —widespread activation during improvisation. Selective deactivations (motivation, emotional tone): amygdala, entorhinal cortex, temporal pole, posterior cigulate cortex, parahippocapal gyri, hippocampus and hypothalamus.

Hypotheses: this unique pattern may have insights into the cognitive workings of the creative process.

Differences? Other studies?

Seems as though it may be like hypnosis and REM sleep with its lateral prefrontal deactivation.

Classically trained pianists: Bengtsson et al. found activations in right dorsolateral prefrontal cortex (as well as premotor and auditory areas) during improvisation. They were not looking at deactivations, however. The two studies used different masking strategies and therefore results would be expected to be different. Also jazz is different than classical. Jazz is characterized by improvisation. The argument is that current findings are based on a more “natural” habitat for improvisation.

Requiring Further Study, and Notes
More extensive deactivation of various limbic systems was observed in this study. This is on top of the expected deactivation of the amygdala and hippocampus, consistent with previous studies of music perception (harmonious and “intensely pleasing” music show these deactivated areas).

Have their findings “characterized a higher qualitative level of musical output (as opposed to that which might be produced by less skilled performers)”? But, despite music simplicity, findings suggest that this is a more generalized neural mechanism than to the highly-trained alone.

Compiling this information with others that actually look at the various studies done on activations of the brain during various tasks (though for activities such as soccer and dance, this fMRI technology is out. It’s one thing to say “put a piano on your lap and see it through these mirrors”—I imagine these pianists really did not have a need to see the piano, in any case—and try to kick this ball without moving your upper body). But, for instance, what NPR seems to have done, albeit without citing any sources, is to find comparisons to other studies. I imagine there may be some major differences between dreaming and jazz improvisation, for instance.

As far as the efficacy of the project, it is always important to question a researcher’s means of obtaining results. More so than the awkward positioning, I think, would be the level of constraint on the improvisation. The point of the study, however, was to observe the differences between the two conditions. Yes, there were certainly elements that were not present in ordinary improvisational conditions (an MRI machine, being horizontal, only using one’s right hand…), however the results did happen and were there. There are differences between the two circumstances, and significant ones, in the brain. Other studies could do with other creative (relatively nonmoving) arts such as painting or writing, to see how those differ in the brain.

My concern had to do more with the one-handedness of the study. The right hand connects directly to the left brain. Granted, the right and left brain of these individuals could communicate with each other, this seems to be something important that was left out for ease, lack of funds, and consistency’s sake.

Bibliography
Limb CJ, Braun AR (2008) Neural Substrates of Spontaneous Musical Performance: An fMRI Study of Jazz Improvisation. PLoS ONE 3(2): e1679.
doi:10.1371/journal.pone.0001679

Study: Jazz Improv Cranks Up Brain's Creativity. http://www.npr.org/templates/story/story.php?storyId=88827029

The affect of media on the color of our dreams

2009-03-02T18:49:00.000-08:00

http://www.newscientist.com/article/dn14959-its-black-and-white-tv-influences-your-dreams.html

This is Your Brain on Dope (amine).

2009-03-01T08:03:00.000-08:00

http://www.mcmanweb.com/love_lust.html

A crazy article going every which way, but I'd like to focus on what dopamine does to the brain in times of love and times of not.

The Colbert ReportMon - Thurs 11:30pm / 10:30c

Helen Fisher

Colbert Report Full Episodes
Political Humor

Dopamine Explained

J Neurophysiol 94: 327-337, 2005. First published May 31, 2005; doi:10.1152/jn.00838.2004
0022-3077/05 $8.00

	ABSTRACT

TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION GRANTS ACKNOWLEDGMENTS REFERENCES

Early-stage romantic love can induce euphoria, is a cross-culturalphenomenon, and is possibly a developed form of a mammaliandrive to pursue preferred mates. It has an important influenceon social behaviors that have reproductive and genetic consequences.To determine which reward and motivation systems may be involved,we used functional magnetic resonance imaging and studied 10women and 7 men who were intensely "in love" from 1 to 17 mo.Participants alternately viewed a photograph of their belovedand a photograph of a familiar individual, interspersed witha distraction-attention task. Group activation specific to thebeloved under the two control conditions occurred in dopamine-richareas associated with mammalian reward and motivation, namelythe right ventral tegmental area and the right postero-dorsalbody and medial caudate nucleus. Activation in the left ventraltegmental area was correlated with facial attractiveness scores.Activation in the right anteromedial caudate was correlatedwith questionnaire scores that quantified intensity of romanticpassion. In the left insula-putamen-globus pallidus, activationcorrelated with trait affect intensity. The results suggestthat romantic love uses subcortical reward and motivation systemsto focus on a specific individual, that limbic cortical regionsprocess individual emotion factors, and that there is localizationheterogeneity for reward functions in the human brain.

	INTRODUCTION

TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION GRANTS ACKNOWLEDGMENTS REFERENCES

Intense romantic love is a cross-culturally universal phenomenon.In a survey of 166 contemporary societies, Jankowiak and Fischer(1992) found evidence of romantic love in 147 of them; theynoted that the 19 remaining cases were examples of ethnographicoversight—the anthropologists failed to ask the appropriatequestions; they found no negative evidence. They concluded thatromantic love constitutes a "human universal...or near universal"(Jankowiak and Fischer 1992). Romantic love is also associated,particularly in early stages, with specific physiological, psychological,and behavioral indices that have been described and quantifiedby psychologists and others (Fisher 1998; Gonzaga et al. 2001;Harris and Christenfeld 1996; Hatfield and Sprecher 1986; Hatfieldet al. 1988; Shaver et al. 1987; Tennov 1979). These includeemotional responses such as euphoria, intense focused attentionon a preferred individual, obsessive thinking about him or her,emotional dependency on and craving for emotional union withthis beloved, and increased energy. Tennov (1979) coined theterm "limerance" for this special state, and Hatfield and Sprecher(1986) developed a questionnaire scale to measure it. The universality,euphoria, and focused attention of romantic love suggest thatreward and motivation systems in the human brain could be involved(Fisher 1998; Liebowitz 1983).

In addition, cross-cultural descriptions of romantic love regularlyinclude reward-related images and suggest strong motivationto win a specific mating partner. For example, the oldest lovepoem from Summeria, "Inanna and Dumuzi," dating 4,000 yr agoand found on cuneiform tablets in the Uruk language is translated,"My beloved, the delight of my eyes..." (Wolkstein and Kramer1983). From the Song of Songs, the Hebrew 10th century poemcomes, "...your love is more wonderful than wine ...the soundof your name is perfume ... . I sought the one my soul loves..."(Wolkstein and Kramer 1983). Furthermore, among the ethnographiescanvassed in the review of Jankowiak and Fischer (1992) is oneby Harris (1995) who cited evidence of the yearning for loveand the motivation to win the beloved among the peoples of Mangaia,Cook Islands, Polynesia. These people have a word for "dyingfor love." They translate it as, "You don’t want anythingelse; you die for love, but you don’t mind if you die;you don’t feel ashamed about loving that person to death.If you really love someone nothing will stop you." Worldwide,romantic love plays a key role in courtship, suggesting thatit evolved as a primary aspect of the human mating system (Fisher1998). Its ubiquity and strong, measurable properties make itan excellent candidate for understanding the human neural systemsassociated with reward, positive emotion, and attention, aswell as the neurobiology of an important phase in human reproductiverelationships, which have genetic consequences.

We used functional MRI (fMRI) methods to test two predictionsabout the neural systems involved in romantic love. First, romanticlove would specifically involve subcortical regions that mediatereward, such as the ventral tegmental area (VTA) and ventralstriatum/nucleus accumbens (Esposito et al. 1984; Hollermanet al. 2000; McBride et al. 1999; Porrino et al. 1984; Robbinsand Everitt 1996; Schultz 2000; Wise and Hoffman 1992). Severalof the behavioral aspects of romantic love suggest that it canbe like cocaine-reward producing exhilaration, excessive energy,sleeplessness, and loss of appetite (Fisher 1998). Consistentwith animal studies of cocaine addiction (David et al. 2004;Kalivas and Duffy 1998; McBride et al. 1999; Wise and Hoffman1992), acute cocaine injection has been shown to activate theVTA in fMRI studies of humans (Breiter et al. 1997). In addition,fMRI studies have shown that secondary rewards like money activatedthe nucleus accumbens/subcallosal region and VTA (Breiter etal. 2001; Delgado et al. 2000; Elliott et al. 2000, 2003, 2004;Knutson et al. 2001). Furthermore, chocolate, acting as a foodreward, activated the VTA and subcallosal region (Small et al.2001). These regions decreased their metabolic activity withdecreasing desire for more chocolate. More data implicatingreward regions and dopamine as an important neurotransmitterfor the feelings and behaviors of romantic love have been summarizedpreviously (Fisher 1998).

In addition to basic reward functions, further evidence fromstudies of monogamous prairie voles suggests that the nucleusaccumbens, striatum, and dopamine could be involved in humanromantic love. When a female prairie vole is mated with a male,she forms a distinct preference for this partner; however, whena dopamine agonist is infused into the nucleus accumbens, shebegins to prefer a male present at the time of infusion, evenif she has not mated with this male (Gingrich et al. 2000; Liuand Wang 2003). Furthermore, a striatal output region throughthe ventral pallidum is strongly implicated as critical to maleprairie vole mate preference behaviors (Lim et al. 2004 ). Also,electrochemical studies in male rats have shown increased dopaminerelease in the dorsal and ventral striatum in response to thepresence of a receptive female rat, more so even than duringcopulation (Montague et al. 2004; Robinson et al. 2002). Thesedata suggest that the nucleus accumbens and dopamine releaseare major factors underlying rodent mate preference. Thus severallines of evidence from both human fMRI and animal studies supportthe prediction that multiple reward regions using dopamine couldbe activated during feelings of romantic love.

Our second prediction about the neural systems involved in early-stageromantic love was that it would be associated with other goaland reward systems, such as the anterior caudate nucleus. Thecaudate plays a role in reward detection and expectation, therepresentation of goals, and the integration of sensory inputsto prepare for action (e.g., Lauwereyns et al. 2002; Martin-Soelchet al. 2001; O’Doherty et al. 2004; e.g., Schultz 2000).While some investigators view romantic love largely as a specificemotion (Gonzaga et al. 2001; Shaver et al. 1987, 1996), othershave proposed that romantic love is a goal-directed state thatleads to varied emotions (Aron and Aron 1991). It tends to behard to control, is not associated with any specific facialexpression, and is focused on a specific reward. The caudatenucleus is a brain region that could represent rewards and goalsin a complex behavioral state like romantic love because ithas widespread afferents from all of the cortex except V1 (Eblenand Graybiel 1995; Flaherty and Graybiel 1995; Kemp and Powell1970; Saint-Cyr et al. 1990; Selemon and Goldman-Rakic 1985)and is organized to integrate diverse sensory, motor, and limbicfunctions (Brown 1992; Brown et al. 1998; Eblen and Graybiel1995; Haber 2003; Parent and Hazrati 1995; Parent et al. 1995;Parthasarathy et al. 1992).

One previous fMRI study (Bartels and Zeki 2000) used methodssimilar to ours, but investigated romantic love in a later stage.Participants in that study had been in love substantially longerthan those in our study [28.8 vs. 7.4 mo; t(32) = 4.28, P <0.001]. Also, participants in that study were less extremelyin love, based on the same standard questionnaire [scores of7.55 vs. 8.54, t(31) = 3.91, P <> is the first fMRI study of early stage romantic love. We alsoshow novel effects in the human VTA that may be associated withdifferent aspects of reward, novel time-dependent effects inthe cingulate and insular cortex, and novel brain activationcorrelations with quantified self-reports of passion intensityand trait affect intensity.

	METHODS

TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION GRANTS ACKNOWLEDGMENTS REFERENCES

Participants

Ten women and seven men were recruited from the State Universityof New York at Stony Brook community, the Rutgers Universitycommunity, and the New York City area by word of mouth and withflyers seeking individuals who were currently intensely in love.All participants preferred their right hand (Edinburgh HandednessInventory, Oldfield 1971) and were not taking antidepressantmedications. The age range was 18–26 yr (mean = 20.6 yr;median = 21 yr). The reported duration of "being in love" was1–17 mo (mean = 7.4 mo; median = 7 mo). All participantsgave informed written consent and each received $50 for hisor her participation. The institutional review boards at StonyBrook and Rutgers approved all procedures.

Interviews and questionnaires

A few days in advance of the scanning session, one of us (H.E.F.)orally interviewed each participant in a semistructured formatto establish the duration, intensity, and range of his or herfeelings of romantic love. Just prior to the scanning session,each participant also completed two self-report questionnaires:1) the passionate love scale (PLS) (Hatfield 1986; example items:"I want ___ physically, emotionally, and mentally"; "SometimesI can’t control my thoughts; they are obsessively on ___")(Cronbach’s for questionnaire reliability in this study= 0.81; Cronbach 1951) and 2) the affect intensity measure (AIM)(Larsen et al. 1987; Cronbach’s in this study = 0.85;example items: "I get overly enthusiastic"; "Sad movies deeplytouch me"), which assesses the general tendency to experienceemotions intensely. After the scanning session, two of us (H.E.F.and D.J.M.) conducted exit interviews to determine whether theparticipants followed the instructions and what they thoughtabout. Also, we tested whether any of the questionnaire datacorrelated significantly with sex, relationship length, or theother questionnaire (or whether any of these variables correlatedwith each other); they did not. That is, there were no significantcorrelations among AIM scores, PLS scores, relationship length,and sex.

Stimuli

The stimuli and length of presentation we used were based ona preliminary investigation that identified a photograph ofthe beloved as better than other stimuli (e.g., touch, voice)for eliciting feelings of intense romantic love (Mashek et al.2000). Also, Mashek et al. (2000) found that the intensity offeeling tended to diminish after about 30 s of exposure to thephotograph. Before the scanning session, each participant provideda photograph of the beloved (positive stimulus) and a similarphotograph of a familiar, emotionally neutral acquaintance ofthe same age and sex as the beloved (neutral stimulus). Photographswere digitized and sized to show the head only. An angled mirrorwas mounted on the RF coil, enabling the participant to vieweach image, which was projected on a screen placed directlyoutside the MRI tube, subtending a visual angle of 17°.To be sure that the quality of the photos provided by participantswas not a factor, we had a group of individuals rate picturequality. The quality of the positive and neutral photos didnot differ significantly (P = 0.88). Also, picture quality didnot correlate significantly with PLS, AIM, relationship length,sex, or separately rated attractiveness of the face (all Ps> 0.14).

Because it is difficult to quell intense feelings of romanticlove, we devised a protocol to decrease the carryover effectafter the participant viewed the positive stimulus. We interspersedthe positive stimulus and neutral stimulus with a distraction,serial countback task. This task involved viewing a number suchas 8,421 on the screen and mentally counting backward in incrementsof seven beginning with this number. A randomly selected differentstarting number was presented each time the task was given.Pilot testing established that 40 s of the countback task effectivelyerased feelings associated with the previous positive stimulusin most individuals. To provide a similar distraction afterthe neutral stimulus (but reduce experiment duration), participantsdid the countback task for 20 s. The different lengths of thecountback task preceding the positive and neutral stimulus presentationswas a possible confound. However, the length of the stimuluspresentation block was likely great enough to reduce any carryovereffects from the countback task. Indeed, inspection of the datashowed that the positive and neutral conditions began at thesame response magnitude rather than different response magnitudes,which would be indicative of carryover effects from the previousblock.

Instructions to participants and exit interviews

In preliminary studies, participants reported that in additionto a photo, thinking about specific events relating to theirbeloved was the best circumstance to elicit intense romanticlove during a 30-s time period (Mashek et al. 2000). Thus theinstructions to the participants were to think about eventsthat occurred with the beloved that were especially pleasurable,but not sexual, while they viewed the positive picture. To controlfor event recall, instructions for the neutral picture wereto think about events with the person in that picture also.During the interview before the experiment, the interviewerestablished pleasurable events that the participant might thinkabout while looking at the beloved, and neutral events, likewatching television, while viewing the neutral stimulus. Theseevents were discussed also just before the fMRI session. Duringexit interviews, the participants reported that they had, indeed,thought about specific events when they looked at the stimuli.For example with regard to the positive stimulus: "I thoughtabout the time we both woke up at 3 AM and walked back fromthe 7/11 store, it was fun walking back and kissing." With fewersexual overtones, one said, "I felt I could really rely on her,I could open up to her, I felt protected by her." One felt arush of euphoria; one felt "happy" and "comfortable." Theseare descriptions of positive, rewarding feelings. Regardingthe neutral stimulus, participants reported that they thoughtabout the specified events with the neutral person that werediscussed before the experiment, and that by comparison, onefelt "bored." All reported that they did the countback task,although we had no behavioral verification. Several reportedthat it was hard to do the countback task after the positivestimulus but not after the neutral stimulus, which is additionalevidence that they carried out the task.

Experimental design and procedures

The protocol consisted of four tasks presented in an alternatingblock design. 1) For 30 s, the participant viewed the positivestimulus; 2) for the following 40 s, the participant performedthe countback distraction task; 3) for the following 30 s, theparticipant viewed the neutral stimulus; and 4) for the following20 s, the participant performed the countback task. The startingimage was either the neutral stimulus or positive stimulus andwas counterbalanced across participants. The four-part sequencewas repeated six times; the total stimulus protocol was 720s (12 min).

Image acquisition and analysis

Data were acquired using a 1.5-T Marconi (Phillips) Edge MRIsystem. We measured the blood oxygen level–dependent (BOLD)response and took in-plane anatomical data for each participant.The images were 1) anatomical, axial T1-weighted Spin-Echo Scans:14-ms TE, 600-ms TR, 90° flip angle, 24-cm FOV, 4-mm slicethickness, 0-mm gap, 256 x 256 matrix size, 20 slices; and 2)functional, T2-weighted Gradient-Echo EPI scans: 70-ms TE (notoptimal), 5,000-ms TR, 90° flip angle, 24-cm FOV, 4-mm slicethickness, 0-mm gap, 64 x 94 matrix size (0 filled into 128x 128 before FFT and the resulting 128 x 128 images were averagedinto 64 x 64 before analysis), 20 slices. Voxel size for thefunctional images was 3.75 x 3.75 x 4.00 mm.

The fMRI data analyses were performed using Statistical ParametricMapping software (SPM 99 Wellcome Department of Imaging Neuroscience,London, UK; Friston et al. 1995). Functional images were realigned,smoothed with a Gaussian kernel of 8 mm, and normalized to theSPM EPI template brain (19 participants were recruited, but2 were dropped from the study because they moved >2 mm).We treated each of the stimulus types (positive, neutral, countback1,countback2) as a separate regressor, modeled as a boxcar functionconvolved with the canonical hemodynamic response; we applieda high-pass filter with a cut-off of 240 s to remove low-frequencysignal components. We created contrast images for each comparisonfor each participant. We then analyzed the contrast images acrossparticipants using a mixed-effects general linear model, treatingparticipants as a random effect and conditions as a fixed effect.Interpretation of the group analyses was facilitated by inspectionof individual results. Time-course data are reported as "response,"a calculation by SPM99 based on raw data that uses the meanof all the conditions as the baseline.

For planned comparisons (hypothesis-driven analyses), we appliedsmall volume corrections with a sphere as a region of interest(P 0.05, corrected for multiple comparisons). The coordinatesfor the centers of the regions of interest were based on a reviewof 15 fMRI articles that had studied reward or romantic love(Table 1). Rewards in the previous studies included acute cocaineinjection, receipt of money, and eating chocolate.

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TABLE 1. Predicted regions of change

To investigate unpredicted regions of activation, we thresholdedthe images at P <> There were no significant differences found.

Using SPM99, we performed correlations between participant questionnairescores and brain responses for the PLS and AIM. Also, becauseanother study showed that there are specific BOLD responsesin humans to faces rated as beautiful compared with faces ratedas average (Aharon et al. 2001), we had five men and five women(nonparticipants) rate the images for overall "attractiveness."We correlated the attractiveness score difference between positiveand neutral for each participant with their neural response(for the positive-minus-neutral contrast). In addition, becausewe thought that differences between our data and the findingsof the study of longer-term romantic love (Bartels and Zeki2000) might be caused by the difference in relationship length,we correlated brain responses and months the participants reportedhaving been in love.

We tested for differences between men and women; however, nonemet the criterion of P <>

Anatomical localization

To aid our identification of regions affected, we used the atlasof Duvernoy (1999) and the Talairach Daemon Client (Version1.1, Research Imaging Center, University of Texas Health ScienceCenter, San Antonio, TX). Data were analyzed for individualson their T1 images, on the mean T1 image for the group, andon the average 305 T1 MNI template in SPM99. To display someof the data, we chose the SPM99 Single Subject T1 (scanned multipletimes) dataset because major landmarks are more visible thanin the other renderings. The calculated error for SPM99 anatomicnormalization within a group is 8 mm between sulci, and thereis 94% overlap among the same gray matter regions (Hellier etal. 2001, 2002). Thus the Talairach descriptions of the locationsof cortical changes that include Brodmann’s areas (BAs)are an approximation only; we include them in the report becausethey are useful to compare with other studies. In addition,the data were smoothed with a Gaussian kernel of 8 mm so thatany single localization point reported in the tables shouldbe considered within an area of 8 mm. Technical considerationslimited us to 20 slices that did not cover the entire brain.Parts of the dorsal neocortex (1–3 cm from the superiorsurface) were not sampled in some participants, whereas theventral temporal lobe was not included in others. Thus we analyzedseparately the amygdala and ventral hippocampus in the nineparticipants (6 women and 3 men) who had data in those regions.

Localization of activation to the medial caudate appeared tobe partially in the ventricle in the normalized group images.To confirm that it was caudate activation, we examined unnormalizedindividual data. We calculated the distance (in mm) from theanterior commissure to the caudate peak activation in each individualand plotted it on a horizontal section from the Montreal NeurologicalInstitute average brain template based on scans from 305 individuals(Fig. 1).

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FIG. 1. Caudate nucleus activation, positive-minus-neutral contrast. A: an enlargement of an axial section through the caudate nucleus from the MNI T1 template that averaged 305 subjects. Black dots show peak activation points for each participant in the present study. Activation points were near the medial edge of the caudate in the vicinity of Talairach coordinates 12, 11, 14 (dark gray areas are lateral ventricles). B: a sagittal section from an individual participant shows the extent of the posterior dorsal caudate activation (arrow). Images in this and all following figures are presented in radiologic convention (participants’ left on the right side of the image). C, caudate.

	RESULTS

TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION GRANTS ACKNOWLEDGMENTS REFERENCES

Positive-minus-neutral stimulus contrast (activations)

Predicted, small volume measurements showed significant differencesin the right medial caudate (Fig. 1A; Table 2), in the rightantero-dorsal caudate body (Fig. 1B, Table 2), in another regionof the right dorsal caudate body, and in the right BA30/retrosplenialcortex (Table 2). Significant bilateral caudate activationswere in the antero-dorsal region (Table 2).

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TABLE 2. Regional activations specific to the picture of the beloved compared to a picture of a familiar, neutral acquaintance

In the ventral midbrain, significant activation was localizedin the region of the VTA/A10 dopamine cells (Fig. 2, A and B).Also, plots of the time-course of the BOLD response show thatneural activation increased in response to the positive imagerelative to the other conditions, whereas there was a decreasein the BOLD signal for each control task relative to the positivestimulus (Fig. 2C). No caudate region showed a similar time-course.

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FIG. 2. Group mean data and an individual subject show the localized ventral midbrain effect. A: positive-minus-neutral contrast. B: positive-minus-countback contrast. Activity in the right VTA region (arrows) specifically increased in response to the positive image compared with both control conditions. The regional activation is highly localized to the medial A10 dopamine cell region with little inclusion of the medial substantia nigra. C: time-course of the BOLD response (means ± SE, 0 = mean of all conditions) for a voxel in the right VTA shows that the signal increased to the positive image (solid line) relative to the others; the signal during control stimuli presentations decreased relative to the positive image, especially for the countback task (short-dash line; 40-s countback task shown). Long-dash line, neutral stimulus. D: in a single subject, a sagittal view shows the anteroposterior extent of the right VTA activation (arrow). E: in the same subject, a coronal view of the right VTA activation (arrow) shows how it is limited to the medial midbrain. Locations of responses shown in the graph are given in Talairach coordinates. L, left side; VTA, ventral tegmental area.

Positive-minus-countback

We had included the countback task to provide a distractionbetween positive and neutral stimuli. However, we reasoned thatit might serve as a supplementary control condition. That is,areas showing strong activation for the positive-minus-neutralsubtraction that also showed activations for a positive-minus-countbacksubtraction may be additional evidence that these representareas associated with intense romantic love. The positive-minus-countbacksubtraction yielded activations overlapping with the positive-minus-neutralsubtraction for the right ventral midbrain and the right postero-dorsalcaudate (Table 2), providing more evidence that activation inthese regions is specific to the image of the beloved.

Self-report of degree of passionate love

Focusing again on the positive-minus-neutral contrast, we conducteda between-subject random effects analysis correlating degreeof the BOLD response and participants’ scores on the PLS.(Recall that there were no significant correlations among PLSscores, AIM scores, relationship length, and sex.) As shownin Fig. 3 and Table 2, PLS scores had high positive correlationswith activation in two of the regions that were significantfor the contrast by itself, the right antero-medial caudatebody (r = 0.60; P = 0.012, Fig. 3C) and the septum-fornix region(r = 0.54; P <> levels of romantic love than others also showed greater activationthan others in this region of the caudate and septum when viewingtheir beloved. As noted by Kosslyn et al. (Kosslyn et al. 2002),the consistency of a between-subject correlation with a subtractionresult provides particularly strong triangulating evidence forthe link of a function with an activated area.

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FIG. 3. Activation in the anteromedial caudate body was correlated with the passionate love scale (PLS) scores of participants. A: caudate location for the correlation (arrow). B: correlation of activity in the caudate with PLS scores. Location of responses shown in graph are given in Talairach coordinates. C, caudate; L, left side.

Attractiveness effects of the positive and neutral faces

The correlation between the BOLD response and independentlyrated attractiveness for the positive image minus the attractivenessof the neutral image was significant for voxels in the leftVTA (r = 0.74, P = 0.009; Fig. 4). This is a different locationfrom activation for the positive-minus-neutral contrast, whichwas in the right VTA (Fig. 2).

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FIG. 4. Activity in the VTA for the positive-minus-neutral contrast was correlated with the independently rated attractiveness of the positive minus the attractiveness of the neutral faces. A: activation is on the left and on the midline (arrow) and different from the localization of activation in Fig. 2, A and B. B: neural activity in response to positive images was greater when the positive face was more attractive than the neutral face.

Neutral-minus-positive stimulus (deactivations)

The only predicted region of change to show a deactivation wasthe amygdala (coordinates: 20, –3, –15, P <>

Length of time in love

Because our participants were in love for a shorter amount oftime than those in the study done by Bartels and Zeki (2000),we correlated degree of activation and participant’s reportedlength of time in love. The correlation was done for the positive-minus-neutralcontrast. As shown in Fig. 5 and Table 3, several regions ofspecial interest showed changes as the relationship lengthened:the right mid-insular cortex; the right anterior and posteriorcingulate cortex; and the right posterior cingulate/retrosplenialcortex. Scatter plots of the correlation in the anterior cingulatecortex and retrosplenial cortex suggest that participants inlonger relationships (8–17 mo) were different from thoseengaged in relatively short relationships (1–7 mo; Fig. 5).Thus it appears that length of time in love is a major factorfor neural activity in the insula and cingulate/retrosplenialcortex when looking at an image of a romantic partner.

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FIG. 5. Length of time in love correlated with activation in specific regions. Regions are indicated on axial (A) and sagittal (C) sections. A: cluster location for the retrosplenial cortex correlation (arrow) is similar to a region correlated with satiation while eating chocolate (Small et al. 2001). B: correlation for the peak voxel in the cluster labeled R in A. C: location of voxel clusters correlated with relationship length in the AC and PC (arrows). D: graph of the correlation between the BOLD response and months in love for the AC. AC, anterior cingulate cortex; PC, posterior cingulate cortex; R, posterior cingulate/BA30 retrosplenial cortex.

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TABLE 3. Regional changes in brain activity that were correlated with the length of the relationship

One brain region showed greater activation the shorter the lengthof time in love: the left posterior cingulate cortex/retrosplenialcortex region (Table 3).

Self-report of general tendency for emotional intensity

Once again using the positive-minus-neutral contrast, we correlateddegree of activation and participants’ scores on the AIM(the AIM was not significantly correlated with the PLS). TheAIM is a self-assessment of general affect tendencies, and thecorrelation with the BOLD response tested for a potentiallyimportant trait difference among participants in a study thatmay involve emotion. The left mid-insular cortex (Talairachcoordinates –42,–6,0) was correlated with AIM score(r = 0.58; P <> and Zeki (2000) reported activation in their study. Thus a leftinsular cortical region was affected by the positive stimulus,but the response varied depending on an individual’s self-reportof how strongly the person experiences affect in general.

	DISCUSSION

TOP ABSTRACT INTRODUCTION METHODS RESULTS DISCUSSION GRANTS ACKNOWLEDGMENTS REFERENCES

Several results support our two predictions that 1) early stage,intense romantic love is associated with subcortical rewardregions that are also dopamine-rich (e.g., Fisher 1998) and2) romantic love engages a motivation system involving neuralsystems associated with motivation to acquire a reward ratherthan romantic love being a particular emotion in its own right(Aron and Aron 1991). Foremost, when our participants lookedat a beloved, specific activation occurred in the right ventralmidbrain around the VTA, dorsal caudate body, and caudate tail.These regions were significant compared with two control conditions,providing strong evidence that they are associated with specificaspects of romantic love.

The VTA contains dopaminergic cells (A10) that send projectionsto several brain regions (Gerfen et al. 1987; Oades and Halliday1987; Williams and Goldman-Rakic 1998), including the medialcaudate where we found specific activations. In addition, boththe VTA and caudate regions activated in this study receivevisual afferents and respond to visual stimuli (Caan et al.1984; Horvitz et al. 1997; Saint-Cyr et al. 1990). AlthoughfMRI is limited to measurements of location and relatively long-termneural responses, and cannot determine neurotransmitters used,other electrophysiological, lesion, fMRI, voltammetry, druginfusion, and self-stimulation studies have established thatthe VTA, dopamine, and the caudate nucleus play major rolesin reward and motivation in the mammalian brain (Delgado etal. 2003; Kawagoe et al. 1998; Martin-Soelch et al. 2001; Phillipset al. 2003; Salinas and White 1998; Schultz 2000; White andHiroi 1998; Wise 1996). Most importantly, Zald et al. (2004)found that predictable monetary reward presentation caused dopaminerelease in the medial caudate body where we found activation.The combined findings implicate reward and motivation functionsas likely aspects of early-stage romantic love and dopamineas one of the candidate transmitters involved.

Cortical areas associated with emotion were involved, also,such as the insular and cingulate cortex. However, as expectedfor a goal-directed state with diverse outcomes, activationof emotion-associated areas varied among individuals dependingon their general affect intensity, passion score, and the lengthof the relationship. Two subcortical areas associated with emotionwere affected: the amygdala and the septum. Amygdala activitywas decreased relative to the neutral stimulus, whereas septalactivity was correlated with the PLS score. Deactivation wasseen in the amygdala by Bartels and Zeki (2000, 2004), also.They suggested that love reduces fearful responses. However,amygdala activity plays a role in the recognition of faces ingeneral, and it is not clear why it was specifically involvedin this study (Kosaka et al. 2003). The septum was one of thefirst regions found to be rewarding during electrical self-stimulation(Olds and Milner 1954). It is activated by VTA self-stimulationreward and medial forebrain bundle self-stimulation reward,and it is involved in several emotional responses in animals,including relief from aversive emotional states (Esposito etal. 1984; Porrino et al. 1984, 1990; Yadin and Thomas 1996).Thus it is consistent with a large body of data that the septumwould be active during a reward state. Finally, the lateralseptum has also been implicated in pair-bonding in prairie voles(Liu et al. 2001).

Regional heterogeneity of ventral tegmental area reward functions

To establish whether the VTA activation occurred because ourparticipants were feeling romantic passion or were stimulatedby an esthetically pleasing face, we correlated facial attractiveness(as rated by others) with neural activation. This correlationshowed that those with more esthetically pleasing partners comparedwith the neutral stimulus showed greater neural activity inthe left VTA than those with less attractive partners comparedwith the neutral stimulus. Several fMRI studies indicate thatthe right VTA, where we found activation for our basic positive-minus-neutralcontrast, is associated with rewards and/or working for rewards(Aharon et al. 2001; Breiter et al. 2001; Elliott et al. 2000,2004; Small et al. 2001); others showed bilateral activationof the VTA (Breiter et al. 1997; O’Doherty et al. 2002).Importantly, Aharon et al. (2001) showed that the left VTA activationwas specifically associated with a face deemed estheticallypleasing (liking), whereas right VTA activation increased duringpresentation of a face that participants would work to see longer(wanting). Thus several fMRI studies corroborate reward effectsin the human VTA (Table 1), but this is the second fMRI studyto show a localization effect within the VTA for two aspectsof reward, wanting and liking (Berridge and Robinson 2003) andto show that this effect is lateralized. Caudate effects forthe positive-minus-neutral contrast were on the right, providingmore evidence that the lateralized VTA effect is not spurious.

The localization of the VTA activation appears to be quite specificin the figures, given the size of the original voxels (3.75x 3.75 x 4.0 mm) and the size of the smoothing filter (8 mm).The specificity appearance is enhanced by the normalized images(2 x 2 x 2 mm). However, the human VTA is 8 mm across, fromanterior to posterior, and 4 mm dorsoventral, well within thearea covered by several voxels. In addition, by smoothing thedata, which tends to enhance effects in large regions of cortex,we probably diluted the observed effect in this small region.The VTA is a small region, however, and given the variabilityinherent in the brains of subjects and the normalization procedures,we cannot be sure that the activation does not include othersurrounding areas.

Regional caudate effects implicate emotion and visual attention functions

Participants who scored higher than others on the PLS showedgreater activation in the right antero-medial caudate body.This region is rich in limbic-associated membrane protein, calbindin,and medial cortical afferents, each of which is associated withhigher-order cognitive and emotional functions (Parent et al.1995). The specific region where activation correlated withthe PLS in our study was activated during anticipation of amonetary reward (Knutson et al. 2001), reward-based stochasticlearning (Haruno et al. 2004), attention (Zink et al. 2003),a spatial and temporal somatosensory discrimination task (Pastoret al. 2004), and simple passive visual processing (Bleicheret al. 2003). Recently, this same right-sided region showedincreased dopamine release for a predictable money reward (Zaldet al. 2004). In addition, our countback task (when comparedwith the neutral stimulus) activated this region. Thus thisarea of the antero-medial body of the caudate is most likelyassociated with rewarding, visual, and perhaps attentional aspectsof romantic love. Intense, focused attention on an individualis one of the cardinal behavioral signs of romantic love (Fisher1998; Hatfield and Sprecher 1986). Visual attention, reward,motivation, and motor planning are often related to caudatefunction (Dagher et al. 1999; Hikosaka et al. 2000; Lauwereynset al. 2002; Zink et al. 2003). In addition, there is one reportof electrical stimulation of the caudate through a chronicallyindwelling electrode in a human epilepsy patient (Delgado etal. 1973). The patient’s words expressing love towardthe investigator were stimulus-bound (J. Delgado and E. E. Coons,personal communication), providing evidence that caudate activationcould be causally related to feelings of romantic love.

Months in love: cortical and subcortical effects

One of the most interesting findings of this study is regionaleffects related to the number of months in love. Notably, severallimbic cortical regions showed a correlation with the lengthof the relationship: anterior and posterior cingulate, mid-insula,and retrosplenial cortex; but also, parietal, inferior frontal,and middle temporal cortex. One small region of the left ventralputamen and pallidum was associated with time in love. The ventralpallidum has been implicated in attachment in prairie voles(Lim and Young 2004; Lim et al. 2004 ). In their fMRI study oflonger-term romantic love, Bartels and Zeki (2000) found activationin the anterior cingulate and mid-insula. Thus we confirm theresults of Bartels and Zeki (2000) that these brain regionsare involved; but in addition, our results suggest that theactivation is dependent on time factors. The time-related activationsmay be related to memory, familiarity, motivation, and attentionfunctions (Velanova et al. 2003; Yamasaki et al. 2002) or anemotional internal state factor such as heart rate (Critchleyet al. 2003; Porro et al. 2003). The correlation in the anteriorcingulate is notable because it is implicated in a cardinaltrait of romantic love: obsessive thinking; it is also involvedin cognition and emotion (Bush et al. 2000; Rauch et al. 2001;Ursu et al. 2003). The right retrosplenial cortex correlationwith length of relationship is of special interest because metabolicactivity there increased during satiation for chocolate (Smallet al. 2001) and was correlated with level of thirst (Dentonet al. 1999). In any case, these results highlight the importanceof these cortical regions for processing stimulus/internal statechange, and the importance of taking time factors into accountin future studies of human relationships. At the same time,these results must be interpreted cautiously because they arecross-sectional, so that, for example, it is possible they representdifferences in the kinds of people that remain intensely inlove over a longer period rather than changes over time.

Evolution of romantic love and its distinction from the sex drive

Studies of prairie voles show that D2 dopamine and oxytocinreceptor stimulation in the nucleus accumbens is associatedwith mate preference in females (Gingrich et al. 2000; Liu andWang 2003), and recent studies of male voles focus on the ventralstriatum/pallidum and the distribution of vasopressin and oxytocinreceptors; however, oxytocin receptors are found throughoutthe striatum as well as in the accumbens in both males and females(Lim and Young 2004; Lim et al. 2004 ). A comparison with ourfindings leads us to speculate about the evolution of romanticlove: with the development of the human cerebral cortex, ancestralhominids employed the phylogenetically newer cortex and dorsalcaudate to initiate partner preference. Romantic love may bea developed form of a general mammalian courtship system, whichevolved to stimulate mate choice, thereby conserving courtshiptime and energy (Fisher 1998). Also, previous fMRI studies ofhuman sexual arousal show regional activation largely differentfrom the pattern we saw for our participants (Arnow et al. 2002;Redoute et al. 2000), consistent with romantic love being distinctfrom the sex drive (Aron and Aron 1991; Fisher 1998).

Comparison with a study of longer-term romantic love

Bartels and Zeki (2000) reported findings of an fMRI study onthe neural correlates of romantic love and reanalyzed theirdata in relation to another study they carried out on maternallove (Bartels and Zeki 2004). As previously stated, their participantswere in love longer and were not as intensely in love as inthis study [28.8 vs. 7.3 mo; t(32) = 4.28, P <> scores of 7.55 vs. 8.54; t(31) = 3.91, P <> used 17 participants and a photograph of the beloved as thepositive stimulus. In this study, we used a familiar acquaintanceas a control, whereas Bartels and Zeki used photographs of friends.Also, we used a distraction task that served as a second controlcondition, the countback task. Many of the basic results areremarkably similar. The ventral midbrain region/VTA and dorsalcaudate nucleus were activated by romantic love in both studies(Bartels and Zeki 2000, 2004); the amygdaloid region was deactivatedin both studies; the mid-insula, anterior, and posterior cingulatewere affected in both studies, but in this study, activationin the cortex was found to be correlated with relationship length.The fact that all of the above regions were affected in bothstudies strongly suggests that they are involved in romanticlove in important ways and that reward and motivation systemsare critical.

In addition, there were differences between the two studiesfor the positive-minus-neutral contrast. Among them, this studyshowed effects in several regions of the caudate, in the septum,and the retrosplenial cortex, and no effect in the dorsal hippocampusor putamen, as was seen by Bartels and Zeki (2000). These differencesmay be caused by the difference between early-stage and longer-termromantic love that could not be assessed with the limited timerange in our study, but could also be caused by individual characteristicresponses that differed between the two samples or by the differencesin experimental methods.

Technical considerations and assumptions

The BOLD responses that we measured were relatively sustainedduring the presentation of the stimuli and also limited by thehemodynamic response function model that we used. If we hademployed other models of response, we might have detected otherareas that could be involved. For example, Moritz et al. (2000)reported that caudate-putamen BOLD responses to finger-tappinghad a short duration, quite different from the cortex. Also,we base our interpretation of the data on the assumption thata BOLD response largely reflects axon terminal activity andfield potentials rather than cell body activity, although thetwo can be correlated (Arthurs et al. 2004; Logothetis et al.2001; Mata et al. 1980; Sokoloff 1999, 1993). In an animal studyusing metabolic mapping of natural somatosensory corticostriateactivity, increased metabolism was associated with corticostriateaxon terminal fields (Brown et al. 2002). Thus we interpretthe measured activation in the caudate to be largely the resultof afferent activity from the cortex, VTA, and intrinsic caudatecell axon collaterals. Likewise, the BOLD response in the VTAmay reflect afferent activity from the caudate or accumbensor other region, not necessarily activity of local cells.

The BOLD response reflects venous blood flow and volume (e.g.,Arthurs and Boniface 2002). Thus activation from the medialcaudate and tail that appeared to be in or lining the ventriclemay be a signal change in the large draining veins on the surfaceof the caudate that forms the ventricular borders (Netter 1983).Such a signal still reflects nearby parenchymal activity, however.Other studies have seen lateral "ventricular activation" thatfollows the curved surface of the caudate (Bleicher et al. 2003;Haruno et al. 2004). We ascribe this activation to the caudatebecause we expect activity there based on known cortical projectionpatterns, the activation is localized and on one side, the caudateprotrudes into the ventricle and could produce a partial volumeeffect, and ventricular activation that might be caused by anartifact such as movement is not seen in other ventricular regions.

The 30-s trial period to look at faces was relatively unconstrained,although instructions were given. Also, differences betweenthe positive and neutral conditions may have been caused bydifferent eye movements or different habituation effects. Ifnumber of eye movements had been a major factor, we expect thatthe frontal eye fields would have shown an effect. It is possiblethat a difference in habituation is an inextricable factor.

In conclusion, the results lead us to suggest that early-stage,intense romantic love is associated with reward and goal representationregions, and that rather than being a specific emotion, romanticlove is better characterized as a motivation or goal-orientedstate that leads to various specific emotions such as euphoriaor anxiety. With this new view of romantic love as a motivationstate, it becomes clearer why the lover expresses an imperativeto be with a preferred individual (the beloved) and to protectthe relationship. Moreover, our results suggest to us that romanticlove does not use a functionally specialized brain system. Romanticlove may be produced, instead, by a constellation of neuralsystems that converge onto widespread regions of the caudatewhere there is a flexible combinatorial map representing motivatingstimuli and memories dependent on the individual and the context(Brown 1992; Brown et al. 1998; Lidsky and Brown 1999). As such,it would be an example of how a complex human behavioral statethat includes emotions is processed. Taken together, our resultsand those of Bartels and Zeki (2000, 2004) with longer-termin love participants show similar cortical, VTA, and caudatelocalization, suggesting that these regions are consistentlyand critically involved in this aspect of human reproductionand social behavior, romantic love. Further experiments willbe needed to determine whether a circumscribed caudate regionand specific afferents are necessary to the experience and behaviorsof romantic love. Importantly, we found potential regional heterogeneityfor different aspects of reward in the VTA and identified somecortical regions whose neural activation was different for individualswho had been in love over a time scale of months or who showedaffect trait differences.

2009-02-18T22:42:00.000-08:00

Curbing the Craving for Nicotine

Goal: To assess the effects of a single session of exercise on regional brain activation while viewing smoking related stimuli.

Primary brain areas studied
Drug use, specifically nicotine, effects three main portions of the brain. Those associated with:
• Reward – caudate nucleus
• Motivation – orbitofrontal cortex
• Visuo-spatial attention – parietal lobe, parahippocampal, & fusiform gyrus.

During a period of nicotine abstinence, mesolimbic and meso cortical (mesocorticolimbic brain system) dopamine circuits are stimulated.

The experiment
10 individuals (six men, four women) were recruited through public poster advertisements.
• 18-50 years of age
• Smoker for at least 2 years
• Smoke at least 10 cigarettes a day
• Average subject: 13.7 cigarettes per day, 8.1 years.

Passive treatment: participants were instructed to sit in the laboratory for 10 minutes. They were not allowed any kind of distraction (reading material, cell phones, internet, etc.) This amount of time was chosen because previous studies revealed this amount of time triggered nicotine cravings in similarly qualified test subjects.

Exercise treatment: participants were instructed on how to use a cycle ergometer. They then spent 2 minutes warming up on the bike and 10 minutes at a subjective
Rating of Perceived Exertion amounting to a light-to-moderately hard workout for each person. Their heart rate was monitored throughout.

After each treatment, the individuals were then led to the functional Magnetic Resonance Imaging (fMRI) scanner.

Before, during, and after each treatment and MRI scanning session, each person was asked to rate their desire to smoke from 1(none) to 7(strong desire).

MRI images

For approximately 15 minutes, those being tested viewed 60 images: 30 smoking-related images (hands holding cigarettes, lit cigarettes, etc.) and 30 neutral images (hands holding, people not smoking, etc.). Images were matched for color contrast and size. In between each image was a white screen with a black fixation cross that allowed for each subject to remain focused. These images lasted randomly for 8, 10, and 12 seconds.

Results

MRI scans revealed that the reward-processing brain areas were indeed stimulated in the control subjects (those not exercising). Stimulated precentral gyrus, parahippocampal gyrus (learning and memory) and caudate areas imply that these individuals experienced an enhanced perceived feeling of pleasure from the images being presented.
Post-exercise, however, revealed significant activations in Broadmanns areas 8-10, the rostral-medial frontal region and posterior cingulated cluster. These results from MRI scanning imply that the amount of exercise performed by each person stimulated the brain in such a way that temporarily inhibited “certain brain regions that were not directly essential to performing and maintaining the exercise, or physiological homeostasis.” Post-exercise, individuals found stimuli less salient. As a result, the images were less likely to elicit cravings.

2009-02-17T17:55:00.000-08:00

Replacing smoking with exercise

TICKLING!?

2009-02-16T09:40:00.000-08:00

"Anatomy of a Tickle Is Serious Business at the Research Lab"

http://query.nytimes.com/gst/fullpage.html?res=9C0DE7DF153DF930A35755C0A961958260&sec=&spon=&pagewanted=1

Blindsight Presentation

2009-02-05T05:23:00.000-08:00

Blindsight

Definition of Blindsight
The patient TN reported on in this NPR story is the latest in a series of cases of blindsight. This paradoxical and counterintuitive phenomenon refers to the ability of humans with a loss of primary visual cortex to make visual discriminations in their blind visual fields without awareness of the stimuli they are discriminating.

Measurement of Blindsight
To get around the lack of visual awareness of blind field stimuli researchers ask their patients to guess whether, where, or which one of a small number of stimuli has been presented within the blind visual field. The types of visual discriminations that have been reported are movement, orientation, wavelength (i.e. , color), spatial localization and combinations of these elementary visual features. Accuracy of responses sometimes reached 90% to 100% in various patients (Weiskrantz, 1995). In addition 'affective blindsight' has been demonstrated: patients can sometimes reliably detect the valence of emotional expressions in the absence of any visual awareness of the faces (Tamietto & deGelder, 2008).

Previous Cases:
This phenomenon was first studied in human patients the 1970s by Oxford University based researchers Lawrence Weiskrantz and Elizabeth Warrington. Their patient GY had extensive damage to his left visual cortex which rendered him functionally blind in his right visual field. They were able to demonstrate GY's capacity to perfectly discriminate the direction of motion within his right visual field. Figure 1 of Weiskrantz's review paper shows the different directions of motion that GY was able to accurately mimic with his arm. The grey area is the impaired hemi-field.

Controversies about the cause of blindsight:
Blindsight is most likely to be due to the use of visual pathways outside of the usual geniculostriate ones, connections that are either subcortical or that go directly to extrastriate areas bypassing primary visual cortex. Some brain researchers have objected that the residual visual function of blindsight could be subserved by fragments or islands of intact striate cortex rather than extrastriate cortex (Weiskrantz, 1995). This is unlikely to be the explanation for GY's motion, wavelength, and emotional expression discrimination capacities because a high-resolution MRI scan reveals only a small patch of striate cortex near the back of the brain on the left side, but he does have some remaining striate cortex.

Why TN is a notable case
The damage to TN's striate cortex is much more extensive than GY's. TN suffered two strokes 36 days apart; the first damaged his occipital cortex unilaterally, and the second destroyed the remaining primary visual cortex in the other hemisphere. Figure 1 of de Gelder et al's paper reporting the case shows the extensive primary visual cortex damage. TN is the only available case in the literature with selective bilateral occipital damage. Yet he can successfully navigate down a long corridor with various barriers set in his way, as demonstrated in the video. His blindsight despite total loss of primary visual cortex effectively refutes the remaining islands of functional visual cortex hypothesis. Extra-striate pathways in humans can sustain sophisticated visuo-spatial skills in the absence of perceptual awareness.

What is blindsight good for?
Blindsight is not demonstrated in every patient with loss of primary visual cortex, but when it is present then it the ability can be cultivated through training for rehabilitation. In the case of TN he was unaware of his residual ability to navigate obstacles using visual information. Behaviorally he was blind across the whole visual field. He walked like a blind man, using his stick to track obstacles and requiring guidance by another person when walking around the laboratory buildings during testing. The researchers were able to demonstrate navigation capacity that he did not know that he still retained in the face of such devastating visual loss. In their quick guide to blindsight for the journal Current Biology Stoerig and Cowey (2007) conclude with the speculation that implicit processes in many domains may always survive when explicit representations are damaged, and therefore that rehabilitation programs could always successfully harness the remaining implicit capacities for restitution.

Bibliography:

de Gelder, B., Tamietto, M., van Boxtel, G., Goebel, R. Sahraie, A., van den Stock, J., Steinen, B.M.C., Weiskrantz, L. & Pegna, A. (2008). Intact navigation skills after bilateral loss of striate cortex. Current Biology, 18, 1128-1129. Link

Lamme, V.A.F. (2006). Zap! Magnetic tricks on conscious and unconscious vision. Trends in Cognitive Science, 10, 193-195.

Rees, G. (1999). Consciousness lost and found. Journal of Psychophysiology, 13, 56-60.

Stoerig, P. & Cowey, A. (2007). Blindsight quick guide. Current Biology, 17, 822-824.

Tamietto, M. & deGelder, B. (2008). Affective blindsight in the intact brain: Neural intrahemispheric summation for unseen facial expressions. Neuropsychologia, 46, 820-828.

Weiskrantz, L. ( 1995). Blindsight - Not an island unto itself. Current Directions in Psychological Science, 4, 146-151. Link to Academic Search Premier

NPR Story on Blindsight

2009-02-05T05:21:00.000-08:00

The NPR story and video can be viewed at:
http://www.npr.org/templates/story/story.php?storyId=98590831&sc=emaf